Romney won't be able to remember where he last stood on any particular topic. Unfortunately for him, he has to lie to backtrack on his previous lies. Lyin' Ryan is no different. If you tell the truth, then you never have to remember which lies are the most recent.
I hope that the entire debate is a slow and painful event for Mitt Romney...sweating bullets the whole time. He deserves every minute of it. And Ann can squirm in her seat trying to hold back and yell, "Stop it!"